Also see the Molecular
Biophysics Group at City University of New York.
Biophysics interfaces physics with biology and medicine and is one
of the most rapidly developing areas of physics. Because of their
specialized training and knowledge, physicists have made major
contributions in revealing the secrets of life and in the treatment of
disease. These contributions are of great value to humanity. Moreover,
biophysics provides challenging research opportunities for physicists.
Physics has contributed greatly to biological science both through conceptual advances and through the development of special techniques for studying matter, including X-rays, NMR, synchrotron and laser light sources, to name a few. Physicists have also been leaders in providing the conceptual framework for understanding both interactions among biological molecules and the way in which these interactions affect living systems. Biophysics draws interest also because biological macromolecules and macro-assemblies are a source of novel physics, and because bio-materials are beginning to find application in technological problems.
Professor Marilyn Gunner combines experimental and theoretical
research to study how proteins control the rates and equilibria of
electron and proton transfer reactions. Acidic and basic amino-acid
side chains control a protein's charge by binding or releasing protons.
Some proteins bind cofactors that accept or donate electrons. A
protein's charge helps determine its folding pattern, the binding of
substrates, and the efficiency of enzyme catalysis. In addition, the
motions of protons and electrons across proteins embedded in cellular
membranes create electrochemical gradients that store energy.
Professor Gunner's experimental studies use time-resolved optical spectroscopy to monitor electron-transfer reactions. The research focuses on photosynthesis, where light energy starts a series of electron tunneling and proton binding reactions. Studies probe the ability of photosynthetic proteins to store the energy of light with very high efficiency. Computer calculations use the Poisson-Boltzmann equation to test how the protein's structure can modify the free energy of charges in different locations. In addition, quantum-mechanical tunneling theories are used to try to understand electron-transfer rates under different conditions. Additional biophysical and biomedical research is conducted by some of our condensed matter physicists and by workers at the Mediphotonics Laboratory of the Institute for Ultrafast Spectroscopy and Lasers.